"""Grandstream UCM preset — web-UI CDR download via the local API.

Grandstream UCM62xx/63xx exposes a REST-style admin API at
  ``https://<host>/api`` with cookie-based auth. The CDR export endpoint
returns CSV; we reuse it via HTTPS transport.
"""

from __future__ import annotations

from datetime import datetime
from typing import Iterable, Optional

from .base import BasePreset, CredentialField, FetchedFile
from ..cdr_transports.https_transport import HTTPSTransport


class GrandstreamPreset(BasePreset):
    PRESET_SLUG = "grandstream"
    LABEL = "Grandstream UCM (62xx / 63xx)"
    CDR_FORMAT = "generic_csv"
    TRANSPORT_METHOD = "api"
    DEFAULT_CRON = "0 2 * * *"

    CREDENTIAL_FIELDS = (
        CredentialField("host", "UCM host / IP", "text"),
        CredentialField("port", "HTTPS port", "number", required=False,
                        help="Default 8089 for Grandstream admin API."),
        CredentialField("username", "Admin username", "text"),
        CredentialField("password", "Admin password", "password", sensitive=True),
    )

    FORMAT_CONFIG = {
        "start_time":    "AcctStartTime",
        "caller_number": "src",
        "called_number": "dst",
        "duration_sec":  "billsec",
        "call_id":       "uniqueid",
        "trunk_group":   "channel",
        "disposition":   "disposition",
        "ts_format":     "%Y-%m-%d %H:%M:%S",
    }

    def _transport(self, cfg: dict, secrets: dict) -> HTTPSTransport:
        return HTTPSTransport(
            host=cfg["host"],
            port=int(cfg.get("port") or 8089),
            username=cfg.get("username"),
            password=secrets.get("password"),
            remote_glob="cgi-bin/api/cdrapi?format=csv",
            extra={"scheme": "https"},
        )

    def validate(self, profile_config: dict, secrets: dict) -> tuple[bool, str]:
        try:
            return self._transport(profile_config, secrets).validate()
        except Exception as exc:
            return False, f"{exc}"

    def fetch(
        self,
        profile_config: dict,
        secrets: dict,
        since: Optional[datetime],
    ) -> Iterable[FetchedFile]:
        # Grandstream's CDR endpoint returns the full export as one CSV
        # per request — dedup is handled later via natural_key_hash.
        transport = self._transport(profile_config, secrets)
        content = transport.fetch(transport.remote_glob)
        yield FetchedFile(
            remote_path=f"grandstream_cdr_{datetime.utcnow():%Y%m%dT%H%M%SZ}.csv",
            mtime=datetime.utcnow(),
            content=content,
            size_bytes=len(content),
        )